Improvement in lifting-jacks



UNITED STATES PATENT OFFICE.

THOMAS SHELDON, OF ENFIELD, CONN., ASSIGNOR TO HIMSELF AND HENRY INMAN, OF PORTLAND; AND E. P. FURLONG, OF WESTBROOK, ME.

. IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 55,430, dated June 5, 1866.

To all whom it mag/concern Be it known that I, THOMAS SHELDoN, of Entield, in` the State of Connecticut, have invented a new and useful Liftin g-J ack for Garriages, Svc.; and I hereby declare the following to be a full,clear, and exact description thereof, which will enable others to make and use my invention, reference bein g had to the accompanying drawings, forming part of this specifiiication, in which is shown a side elevation of my invention, representing the different portions thereof.

In the accompanying drawings, Arepresents an upright secured to the base B and iitted with the cap. C D represent a sliding arm having the lip et and the attachment e, having a slot which embraces the upright A. The

sliding arm D bears the head h, to receive the weight to be raised.

L indicates the hand-lever. b represents a brace vcomposed of two parts attached at one 4end to either side of the cap O by the pivotv P, at the other, `on both sides ot' the lever L, by the pivot o.

E shows a horizontal sliding` piece connected with the lever L by thejoint n, and having two slots, one at r to receive the upright A, the other at s, through which the sliding arm D passes as it is raised or lowered.

H shows a rest or support for the sliding arm D. The rest slides up or down upon the upright A by means of a slot similar to that in the attachment e. rlhe slots inthe horizontal sliding piece E, attachment e, and rest H are all made slightly larger than the upright A and the sliding arm D, over which they pass and work loosely, in order that when a weight is imposed upon the head h they will bind them, and thus hold the weight stationary at any desired height; and the greater the weight the rmer it is by these means held.

When the hand-lever L is turned downward to its utmost extent the straight part t thereof will be parallel with the upright A, the part t resting against the upright A. In this position, as the pressure of the weight is in avertical line passing through the center ot' the pivots l? and o, it is evident that no amount of pressure upon the head h can raise the hand` lever and depress the head h. By this simple arrangement any weight can be securely sustained.

As the hand-lever is raised and lowered the brace b swings outward and backward. When the sliding` arm D is raised and a weight resting thereupon the rest H is slipped up, so that the attachment e is brought in contact there with. This will sustain the weight while the lever is again raised, the slide E thereby lowered, and the weight cau then be lifted to any yadditional desired height. The lip a is de- 

